Women Undercover

I was watching a few lakorns where the woman goes undercover in some family house in order to find out the truth to a certain incident and the person she suspects the most is usually the main lead, who she ends up falling in love with. I was wondering if anyone knew of dramas from any country with a similar plot. For those who are familiar with lakorns I'll list the ones I was referring to so you have an idea of what I am looking for.

Paen Rai Long Tai Wa Rak, Khun Mae Suam Roy and Mook Liam Petch

 Beep:

I’d recommend the Korean drama “Cruel City”. It has two, but going any further would be spoiling. 

All in all a very good drama. 

Oops, just saw your watch list, seems you’ve already watched and enjoyed it 

Thanks for the suggestion even though I watched it, it is one of my favorites

Dok Ruk Rim Tang and Taddao Bussaya both have the female lead pretending to be a boy to get into their dead father's house to try and get information. I've only seen the beginning of Dok Ruk Rim Tang, and she's there to try to find out how her father died I don't know if she suspects the male lead specifically.

In Plerng Naree  and Fai Lang Fai they both infiltrate the companies the male lead is connected with, and the male leads suspect them, but they have no proof that they are up to no good, which is a bit like Paen Rai Long Tai Wa Rak. 

There's also something like Mask, which she's taking the place of someone who's already died and she's isolated and doesn't know if she can trust the male lead.